It has been known to use head trackers in simulators which are used in various types of equipment, such as flight simulators, vehicular simulators such as armored units or other types of land vehicles as well as water born vehicles. Many of the known types of head trackers provide multiple degrees of information, such as six degree of freedom in position and orientation information so that appropriate views or displays can be activated only as needed. Known multiple degree of head trackers have been based on various different technologies. These have included ultrasound, optical, inertial, or magnetic.
While known head trackers are effective for their intended purpose, they are often expensive and require extensive set-up times. Additionally, known head trackers often require substantial software interaction to address the various signals coming therefrom. This can include dedicating resources to carry out extensive plotting.
Certain types of simulations require information for only a single degree of freedom, for example, in the azimuthal direction. For example, armoured simulators, such as armored wheeled or tracked vehicles present to the vehicle commander a plurality of spaced-apart displays simulating cupola or tank turret periscopes which face different directions. In these instances, the vehicle commander would only need to rotate his or her head about a substantially fixed vertical axis to view displays presented at several different angles. Viewing directions could include, for example, straight ahead, 20 to 22 degrees to the right, 45 degrees to the right, and similar angles to the left.
Thus, there continues to be a need for head trackers which provide more limited amounts of information, corresponding to fewer degrees of freedom, than heretofore known. Preferably, such head trackers could be implemented more cost effectively than multiple degree of freedom head trackers of known types. Additionally, it would be preferable if set-up times could be reduced so that the speed of training or conducting exercises can be increased.